Dr Arya was shot while on a morning walk near his Vikas Nagar home on October 27,2010. According to the CBI,the killers,A P Tiwari and Vinod Sharma,were hired by Dr Shuklas deputy,Deputy CMO Dr Y S Sachan,through a friend,R K Verma.

Shukla had good connections in the previous BSP government. He is also accused in two cases of financial irregularities in the National Rural Health Mission in Lucknow. The Lucknow Police arrested him last year under pressure from a court,but Shukla subsequently got bail.

A CBI officer said Shukla came under the scanner after a polygraph test given to retired Additional Chief Medical Officer (ACMO) A K Singh last month. Singh was Shuklas subordinate during his tenure as Lucknow CMO.

Sources said Shukla,who had been looking after the implementation of NRHM since 2007,was upset after the family welfare department was separated,and Dr Arya was posted as CMO of family welfare with responsibility of NRHM. Dr Arya detected serious irregularities in certain NRHM cotracts awarded during Shuklas tenure.